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Reliable Isolation of Central Nervous System Microvessels Across Five Vertebrate Groups
Published on: January 12, 2020
Water homeostasis in the brain: basic concepts
1Neural and Vascular Biology Theme, Ordway Research Institute, 150 New Scotland Avenue, Albany, NY 12208, USA. hkimelberg@ordwayresearch.org
Abstract:
The mammalian CNS is separated from the blood by tight junctions, collectively termed the blood-brain barrier (BBB). This imposes unique features of solvent and water movement into and out of the CNS. The basic equations for water fluxes driven by osmotic gradients are presented. The anatomy of the BBB and the physiology of the transport processes for cerebrospinal fluid production, extracellular fluid production and intercellular water and solute transport are then described. A quantitative analysis of the need for aquaporin-based water movements to accompany the known rates of CSF production is also presented. Finally, the mechanisms and roles of cellular and vasogenic edema in the CNS, especially in relation to aquaporins, are described.
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CSF is produced mainly in the choroid plexus, a network of capillaries and ependymal cells located within the ventricular system of the brain.

